The influence of plant extracts and bacteria (Bacillus thuringiensis) (Bt) strains on different larval stages of Trilocha varians (Walker) were studied under laboratory conditions. Results indicated that larval mortality increased with exposure time. Early instar (2^nd instar larvae) were more susceptible to Bt and plant extracts than older instars (3^rd instar larvae). At day seven, Turex (Bt subspecies kurstaki and aizawai) and Dipel (Bt subspecies kurstaki), showed 76.43 and 70.09% mortalities in 2^nd instar larvae, respectively. Mortality rates of 3^rd instar larvae were 71.17% and 65.40% for Turex and Dipel, respectively. Azadirachta indica and Eucalyptus globulus extracts caused 63.12 and 51.09% mortalities of 2^nd instar larvae respectively at the highest dose rate (25 ppm/mL). These results are consistent with previous research and suggest that optimizing both dose and application duration can significantly improve pest control effectiveness. The study highlights the potential of herbal products as effective, safer and environmentally friendly organic insecticides. These products can be integrated into integrated pest management (IPM) programs and provide a sustainable alternative to traditional chemical insecticides.